May 13 (Reuters) - Indian shares led a rebound in emerging market stocks on Wednesday following a bumper fiscal stimulus, while some currencies in the developing world firmed as bets of negative U.S. interest rates crimped the dollar.

Overall sentiment, however, was fragile as rising cornavirus cases in countries lifting lockdowns fed fears of a second wave of infections and U.S.-China tensions simmered.

Bourses in South Korea, mainland China and Turkey gained between 0.2% and 1%, while those in Russia, South Africa and most of central and eastern Europe were firmly in the red.

MSCI’s index of emerging markets shares was up 0.12%

Indian stocks soared more than 4.5% as investors cheered the government’s $266 billion stimulus package – roughly 10% of the country’s GDP - to shore up its virus-stricken economy.

But gains were pared and the rupee slipped as euphoria was tempered by concerns over increased government borrowing.

“Financing aspects will be keenly watched to gauge whether bulk of it would be raised through borrowings or alternate sources like COVID-19 bonds among others,” said Radhika Rao, an economist with DBS Bank in Singapore.

“Until clarity is available, funding burden will fall on bond markets in the near-term and to stabilise markets, focus will return to (the central bank’s) participation.”

A speech by Federal Reserve Chairman Jerome Powell later in the day is awaited after U.S. President Donald Trump on Tuesday again pushed the Fed to adopt negative rates as data showed that U.S. consumer prices marked their biggest decline since the Great Recession.

“Powell is likely to speak out against negative interest rates,” said Commerzbank analyst Antje Praefcke. “It is questionable whether the market will be convinced by that right away as it is being showered by catastrophic fundamental data.”

South Africa’s rand fell 0.3%, while Turkey’s lira trod water.

Turkey’s March current account deficit came in wider-than-expected, while comments from former New York Fed Chief William Dudley that the country’s foreign cash needs are not the sort of thing the Fed is likely to relieve poured more cold water over the prospect of Turkey possibly getting a swap line from the Fed.